Thesis (Ph. D.)--Montana State University--Bozeman, 2006. / Typescript. Chairperson, Graduate Committee: Jay J. Rotella. Includes bibliographical references.

Thesis (Ph. D.)--University of Texas at Austin, 2004. / Supervisors: David Cannatella and David Hillis. Vita. Includes bibliographical references. Also available from UMI.

Thesis (M.Sc.)--York University, 2005. Graduate Programme in Biology. / Typescript. Includes bibliographical references (leaves 209-216). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://gateway.proquest.com/openurl?url%5Fver=Z39.88-2004&res%5Fdat=xri:pqdiss &rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:MR11749

The subtidal whelk Burnupena papyracea (Brugière) co-occurs with a voracious predator, the rock lobster Jasus lalandii (Milne Edwards), in situations where other potential prey are largely eliminated. This has been ascribed to a symbiotic bryozoan, Alcyonidium nodosum (O’Donoghue and de Watteville), which characteristically encrusts the shells of B. papyracea and deters feeding by Jasus. In this study it is shown that this is not due to physical effects of either induced physical defences in the bryozoan or increased shell strength due to the presence of the bryozoan. Neither spectroscopic screening of chemical extracts of the bryozoan nor analysis for volatile constituents revealed any apparent chemical components that are likely to deter feeding. Chemical extracts also failed to show larvicidal effects in a standard toxicity assay using the brine shrimp Artemia salina (Leach). Despite this, bioassays using individual Jasus indicated a chemical basis for feeding deterrence. The assays were run separately on three sets of Jasus and some repeats of assays gave contradictory results. However, assays showing no significant effect of treatment occurred with moulting Jasus, involved very low overall feeding rates and so gave a less convincing result. In other assays Jasus always avoided Burnupena papyracea with live Alcyonidium encrusting the shell, and food pellets containing Alcyonidium or an Alcyonidium extract. Significant preferences were shown for an unencrusted whelk, B. cincta (Röding), over B. papyracea; for B. papyracea with the bryozoan scraped off over natural B. papyracea; for B. papyracea on which the bryozoans had been killed with liquid nitrogen over untreated B. papyracea; and for food pellets prepared from ground, dried mussel over pellets prepared with dried mussel mixed with A. nodosum or its crude organic extract. It is concluded that the protection which Alcyonidium confers on Burnupena papyracea does have a chemical basis, but that the chemical responsible is either present in only trace quantities, or that it is a structurally unremarkable compound which is distasteful to Jasus. This work highlights both the advantages of using ecologically relevant bioassays (positive results when standard techniques give a negative result) and also the disadvantages (logistic constraints on sample sizes when using large test animals and individual variability in a relatively sophisticated test animal).

From Thesis: Why the animal as our point of departure in this discussion of prehistoric art, and why as a sacred symbol? Prehistoric art stretched over an immensely long period, from the first evidence of the activities of Neanderthal tribes during the Mousterian period, ± 35,000 B.C., to the end of the Magdalenian, ± 8,000 B.C. We are dealing with a time-span of nearly 30,000 years, during which a strictly Zoomorphic attitude existed. The animal was the dominant feature. It was constantly used in the decoration of cave walls, on engraved stone slabs, and on all kinds of utilitarian objects.

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Digitized by Kansas State University Libraries

Typescript, etc. / Digitized by Kansas State University Libraries

Digitized by Kansas State University Libraries